Method for manufacturing resistor

Abstract

To provide a resistive element that does not contain a lead component and is capable of suppressing the resistance temperature coefficient.SOLUTION: The resistive element has a pair of electrodes and a resistive film arranged between the portion of the respective electrodes. The resistive film includes glass, conductive particles, and a conductive component containing ruthenium oxide or iridium oxide. The conductive component is contained in the resistive film in the ratio of 100 ppm or more and 5000 ppm or less by mass, and the resistance value is 50 ohms or more and 1000 ohms or less.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a resistor and a method for manufacturing the resistor.

Background Art

[0002] Conventionally, as methods for forming a resistor of an electronic component, a thick film method using a resistive paste and a thin film method of forming a film by sputtering or the like using a film forming material are well known.

[0003] The thick film method forms a resistor by printing and firing a resistive paste on a ceramic substrate. Since the equipment is inexpensive and the productivity is high, it is widely used in the manufacture of resistors such as chip resistors and hybrid ICs.

[0004] The resistive paste used in the thick film method is substantially composed of conductive particles, glass frit, and an organic vehicle for making them into a paste suitable for printing. As the conductive particles, ruthenium dioxide (RuO 2 ) or pyrochlore type ruthenium-based oxide (Pb 2 Ru 2 O 7-x , Bi 2 Ru 2 O 7 ) is generally used. According to Patent Document 1, by using an Ru-based oxide as the conductive particles, a ceramic resistor element having a TCR of about 0.01% or less per 1 °C can be provided for a resistance region ranging from a value lower than 100 ohms per square to a value exceeding 180,000 ohms per square.

[0005] Further, Patent Document 2 discloses adding a glass corresponding to glass frit as an inorganic binder, and discloses using a glass containing a large amount of lead such as lead silicate glass or lead borosilicate glass as the glass.

[0006] The reason why lead borosilicate glass is used for the glass frit is that it has good wettability with Ru-based oxides, has a thermal expansion coefficient close to that of the substrate, and has suitable viscosity during firing. (Non-Patent Document 1) However, in recent years, due to the demand to eliminate the use of toxic lead from electronic devices, there is a demand for a lead-free conductive powder to replace lead ruthenate powder as a conductive powder for thick-film resistors in the high resistance range. In order to completely eliminate lead from thick-film resistors, it is also necessary to eliminate lead from the glass frit that is used at the same time. However, even if all lead is eliminated from the resistor paste, it is still required to obtain a resistor with good electrical properties such as the temperature coefficient of resistance.

[0007] In Patent Document 3, iridium oxide (IrO 2 It has been proposed to use iridium oxide powder as the conductive powder for forming thick-film resistors. A paste for forming thick-film resistors using iridium oxide powder as the conductive powder is particularly useful as a paste for forming thick-film resistors in the high resistance range that does not contain lead and can replace lead ruthenate powder.

[0008] There is also interest in using thin film resistors rather than thick film to produce lead-free resistors. Although single-layer films of Ni or Cr and Ni-Cr alloy films have been put to practical use, the low resistance of metal films makes it impossible to create high-resistance resistors.

[0009] Patent Document 4 describes a thin film resistor that is composed of two or more thin layers of blocky metal with different resistance temperature coefficients, each thin film having a positive and negative resistance temperature coefficient, and that has a predetermined resistance value and a small resistance temperature coefficient by controlling the film thickness of the thin films and the ratio of each film thickness.

[0010] However, the resistor using the above-mentioned metal thin film has a problem in that a paste material cannot be used because the metal thin film is formed on a substrate.

[0011] As shown in Non-Patent Document 2 and Patent Document 5, the development of conductive adhesives and resin resistors using resins and conductive fillers has also been advanced. However, it has been difficult to obtain resistors with a low temperature coefficient of resistance, and such resistors have not been obtained yet.

Prior Art Documents

Patent Documents

[0012]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Non-Patent Documents

[0013]

Non-Patent Document 1

Non-Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0014] In view of the problems of the above prior art, one aspect of the present invention aims to provide a resistor that does not contain a lead component and can suppress the temperature coefficient of resistance.

Means for Solving the Problems

[0015] To solve the above problems, the present invention provides a pair of electrodes, and A resistor film disposed between the pair of electrodes, and The resistor film has glass, conductive particles, and a conductive component containing ruthenium oxide or iridium oxide. Provided is a resistor in which the content ratio of the conductive component in the resistor film is 100 ppm or more and 5000 ppm or less by mass ratio, and the resistance value is 50 Ω or more and 1000 Ω or less.

Advantages of the Invention

[0016] According to one aspect of the present invention, a resistor that does not contain a lead component and can suppress the resistance temperature coefficient can be provided.

Brief Description of the Drawings

[0017]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Modes for Carrying Out the Invention

[0018] Hereinafter, the resistor of the present invention and the method for manufacturing the resistor will be described. [Resistor] The inventor of the present invention has studied a resistor that does not contain a lead component and can suppress the temperature coefficient of resistance. And it has been found that a resistor with a suppressed temperature coefficient of resistance can be obtained by using a resistor containing conductive particles having a positive temperature coefficient of resistance and a conductive component having a negative temperature coefficient of resistance.

[0019] FIG. 1 shows an explanatory diagram of the resistor of the present embodiment. FIG. 1 schematically shows a cross-sectional view of the resistor 10 in a plane parallel to the direction in which a pair of electrodes 111 and a resistor film 112 described below are arranged. In FIG. 1, for convenience of explanation, the conductive particles and the conductive component are shown larger than actual.

[0020] As shown in FIG. 1, the resistor 10 of the present embodiment can have a pair of electrodes 111 and a resistor film 112 disposed between the pair of electrodes 111.

[0021] The resistor film 112 can have glass 12, conductive particles 13, and a conductive component 14 containing ruthenium oxide or iridium oxide.

[0022] And the content ratio of the conductive component 14 in the resistor film 112 can be 100 ppm or more and 5000 ppm or less by mass ratio. Also, the resistor 10 can have a resistance value of 50 Ω or more and 1000 Ω or less.

[0023] In the resistor of the present embodiment, in the resistor film 112 disposed between the pair of electrodes 111, an electric current is generated through the conductive particles 13 and the conductive component 14, and electricity can flow between the pair of electrodes 111.

[0024] Specifically, for example, as indicated by the dotted line A in FIG. 1, it is considered that the conductive component 14 disposed between the conductive particles 13 forms a conductive path by hopping conduction and electrically connects between the conductive particles 13. And it is considered that an electric current flows between the electrodes 111 through the conductive path formed by the conductive particles 13 and the conductive component 14.

[0025] Each member included in the resistor of the present invention will be described. (1) Resistance film As shown in FIG. 1, the resistance film 112 of the resistor 10 of the present embodiment has glass 12, conductive particles 13, and a conductive component 14, and the conductive particles 13 and the conductive component 14 can be arranged in the glass 12. (1-1) Conductive particles As will be described later, the resistor of the present embodiment can be formed, for example, by applying a resistor film paste containing conductive particles and coated glass particles between the electrodes 111, followed by drying and firing. Therefore, the conductive particles are preferably made of a material whose resistance does not change during the heat treatment when heating the resistor film paste. For example, noble metals such as Au (gold), Ag (silver), Pd (palladium), and RuO 2 (ruthenium oxide), IrO 2 (iridium oxide), etc., and it is preferably one or more materials selected therefrom. Note that, as with Ag powder and Pd powder, a plurality of types of conductive particles can be used simultaneously.

[0026] The shape of the conductive particles is not particularly limited, and for example, it can have one or more shapes selected from spherical, flaky, etc. Also, the average particle size of the conductive particles is not particularly limited, but for example, it is preferably 0.1 μm or more and 10 μm or less, and more preferably 0.3 μm or more and 2 μm or less.

[0027] The manufacturing method of the conductive particles is not particularly limited, and depending on the type of material used, etc., it can be manufactured by various manufacturing methods.

[0028] The content ratio of the conductive particles 13 in the resistor 10 is not particularly limited and can be selected according to the resistance value required for the resistor 10, etc. For example, when it is required to suppress the resistance value of the resistor 10, that is, to make it small, the content ratio of the conductive particles 13 can be increased. Also, when it is required to increase the resistance value of the resistor 10, the content ratio of the conductive particles 13 can be decreased. (1-2) Conductive component The conductive component 14 is preferably a conductive material that does not form a compound with the glass 12, and for example, it can contain iridium oxide or ruthenium oxide.

[0029] The resistor of this embodiment can be formed, for example, by applying a resistor film paste (hereinafter, may be simply referred to as "paste") containing conductive particles and coated glass particles between electrodes 111, followed by drying and firing.

[0030] Since the content of the conductive component 14 is very small, it is difficult to analyze and specify the specific state in the resistor film 112. However, the conductive component 14 is derived from the conductive component disposed on the surface of the coated glass particles, and is considered to be disposed at the grain boundary portion between the coated glass particles when the coated glass particles are heat-treated. And, as shown in FIG. 1, the conductive component 14 is preferably arranged discontinuously and spaced apart so as to easily form a conductive path by hopping conduction.

[0031] Therefore, the conductive component 14 is preferably a material that can be easily formed in a film shape on the surface of the glass particles and whose film is easily broken when the coated glass particles are heat-treated. Thus, as described above, the conductive component 14 preferably contains, for example, ruthenium oxide or iridium oxide. Note that the conductive component 14 can also be composed of ruthenium oxide or iridium oxide.

[0032] As described above, it is difficult to analyze and specify the state of the conductive component 14 in the resistor film 112, but it is considered that the conductive component 14 forms a conductive path by hopping conduction between the conductive particles 13. This is also clear from the fact that when the component analysis of the resistor film 112 of the resistor 10 of this embodiment is performed, the conductive component 14 is contained, and a resistor can be formed with the resistance value suppressed as compared with the case where the conductive component 14 is not added. And, the conductive component 14 is considered to exhibit a negative resistance temperature coefficient by forming a conductive path by hopping conduction as described above.

[0033] The resistor 10 of this embodiment preferably has a resistance value of 50 Ω or more and 1000 Ω or less, and the content ratio of the conductive component 14 in the resistance film 112 is preferably 100 ppm or more and 5000 ppm or less by mass ratio. By setting the content ratio of the conductive component 14 in the resistance film 112 to 100 ppm or more by mass ratio, a sufficient conductive path can be formed between the conductive particles 13, and the resistance value and the resistance temperature coefficient of the resistor 10 can be set to desired values. Further, when the resistance value of the resistor 10 is within the above range, if the content ratio of the conductive component 14 in the resistance film 112 is made more than 5000 ppm by mass ratio, the content ratio of the conductive component 14 in the resistance film 112 becomes high, and a conductive path other than hopping conduction may be formed, and there is a risk that the resistance temperature coefficient cannot be sufficiently suppressed. Therefore, it is preferable that the content ratio of the conductive component in the resistance film 112 is 5000 ppm or less by mass ratio.

[0034] Fig. 2 shows the result of analyzing the resistance film 112 of the resistor 10 of this embodiment by SSRM. SSRM (Scanning Spread Resistance Microscope) is a scanning type spreading resistance microscope, which is a device that scans the sample surface with a conductive cantilever and can two-dimensionally measure the distribution of the resistance value. According to SSRM, local resistance measurement at the nanometer level can be performed.

[0035] As shown in Fig. 2, the resistance film 112 of the resistor 10 of this embodiment has a region of conductive particles 13 with a low resistance value and a region of glass 12 with a higher resistance value than the conductive particles 13. And it can be confirmed that low resistance regions 21 with a resistance value lower than that of the glass 12 are scattered at the interface between the glass 12 and the conductive particles 13 and between the conductive particles 13. Such low resistance regions 21 are presumed to be due to the conductive component 14.

[0036] That is, when measuring the resistance value distribution by the scanning spreading resistance microscopy method, the resistance film 112 of the resistor 10 of the present embodiment can have a low resistance region with a lower resistance value than the glass 12 between the conductive particles 13. Such a low resistance region forms a conduction path by hopping conduction as described above and exhibits a negative temperature coefficient of resistance, so that the temperature coefficient of resistance of the resistor 10 can be particularly suppressed. (1-3) Glass Regarding the glass 12, its composition and the like are not limited. As the glass 12, for example, glass of a composition system containing no lead such as zinc borosilicate glass, calcium borosilicate glass, and barium borosilicate glass can be used. (1-4) Other components The resistance film 112 is formed by adding a vehicle or the like in addition to the material constituting the resistance film 112 to make a paste for the resistance film, and then applying, drying, and firing the paste between a pair of electrodes 111. Therefore, the resistance film 112 may contain inevitable components due to the vehicle or the like in addition to the aforementioned glass 12, conductive particles 13, and conductive component 14.

[0037] In addition, the resistance film 112 can also contain additives for the purpose of adjusting the sheet resistance value, the temperature coefficient of resistance, the coefficient of thermal expansion, improving the breakdown voltage, and other modifications. Examples of the additives include MnO 2 , CuO, TiO 2 , Nb 2 O 5 , Ta 2 O 5 , SiO 2 , Al 2 O 3 , ZrO 2 , ZrSiO 4 and the like are generally used. Also, the proportion of the additive is generally 0.05% or more and 20% or less by mass with respect to the total mass of the aforementioned conductive particles, conductive component, and glass. (2) Electrodes The material of the pair of electrodes 111 is not particularly limited, and various electrodes used for resistors can be used. Note that the resistor 10 of the present embodiment can be formed on various insulating substrates.

[0038] It is preferable that each member of the resistor of this embodiment does not contain lead. Not containing lead as used herein means that it is not intentionally added, and does not exclude the case where it is contained as an inevitable component.

[0039] According to the resistor of this embodiment described above, the resistor film 112 includes the conductive particles 13 and the conductive component 14. Therefore, by adjusting the addition amount etc. of the conductive particles 13, the resistance value of the resistor 10 can be easily controlled, and the resistance temperature coefficient can be suppressed. Accordingly, even without using a material containing a lead component, a resistor having a desired resistance value and suppressing the resistance temperature coefficient can be obtained.

[0040] As described above, the resistor of this embodiment has a very small amount of the conductive component contained therein and a very small size of the conductive region of about several nm. Therefore, at the technical level of the analysis technology at the time of filing, it is difficult to analyze and specify the state of the conductive component. For this reason, the resistor of this embodiment can also be described as a resistor obtained by the method for manufacturing a resistor described below. [Method for Manufacturing Resistor] The method for manufacturing the resistor of this embodiment will be described. According to the method for manufacturing the resistor of this embodiment, the resistor described above can be manufactured. Therefore, the description of the matters already described will be omitted.

[0041] The method for manufacturing the resistor of this embodiment can include the following coated glass particle forming step, paste preparing step, and resistor film forming step.

[0042] Hereinafter, each step will be described. (1) Coated Glass Particle Forming Step The coated glass particle forming step can form coated glass particles by disposing a conductive component containing ruthenium oxide or iridium oxide on at least a part of the surface of the glass particles. (1-1) Coated Glass Particles (1-1-1) Glass Particles The glass particles of the coated glass particles are the same material as the glass 12 in the aforementioned resistance film 112, and their composition is not particularly limited. As the glass particles, for example, glass particles and powders of a composition system that does not contain lead, such as zinc borosilicate glass, calcium borosilicate glass, and barium borosilicate glass, can be used.

[0043] The method for manufacturing the glass particles is not particularly limited either. Generally, glass can be manufactured by mixing predetermined components or their precursors in a formulation that can obtain the desired resistance value to prepare a glass raw material, and then melting and rapidly cooling the glass raw material. The melting of the glass raw material can be carried out, for example, at a melting temperature of around 1400°C, depending on the glass raw material. Also, rapid cooling is usually performed by immersing the melt in cold water or flowing it onto a cold belt. Then, the glass obtained after rapid cooling can be pulverized as needed to obtain glass particles and glass powder. The pulverization of the glass can be carried out to the desired particle size using a ball mill, vibration mill, planetary mill, or bead mill, etc. In addition, in order to adjust the particle size of the glass particles as needed, sieving or the like can be further performed after pulverization.

[0044] The particle size of the glass particles is not limited either, but the average particle size of the glass particles is preferably 5 μm or less, and more preferably 3 μm or less. In this specification, the average particle size means the particle size at 50% of the volume integration value in the particle size distribution obtained by the laser diffraction / scattering method.

[0045] By setting the average particle size of the glass powder to 5 μm or less, the variation in the surface resistance value of the resulting resistor can be suppressed, and the load characteristics can be improved.

[0046] The lower limit value of the average particle size of the glass powder is not particularly limited, but the average particle size of the glass powder is preferably 1 μm or more, and more preferably 1.5 μm or more. (1-1-2) Conductive component The conductive component is the same component as the conductive component 14 described in the resistor mentioned above, and can be disposed on at least a part of the surface of the glass particles. The conductive component can contain ruthenium oxide or iridium oxide, and can also be composed of ruthenium oxide or iridium oxide.

[0047] FIG. 3 shows a cross-sectional schematic view of the conductive particles 13 contained in the resistor film paste 30 obtained in the paste preparation process described later and the coated glass particles 31 in an arbitrary cross-section. As shown in FIG. 3, the coated glass particles 31 can have glass particles 311 and a conductive component 312 disposed on at least a part of the surface of the glass particles 311. The conductive component 312 is a component that forms a conductive path by hopping conduction in the resistor film of the resistor, as described above, and can be provided discontinuously and spaced apart in the resistor film, for example. Therefore, as shown in FIG. 3, the conductive component 312 may be formed in a film shape on the entire surface of the glass particles 311, but a part or all of it may be dispersed and arranged in an island shape (dot shape) on the surface of the glass particles 311. Even if the conductive component 312 is formed in a film shape on the entire surface of the glass particles 311, it is considered that the conductive component 312 will break during the heat treatment in the resistor film forming process described later and will be arranged discontinuously and spaced apart in the resistor film.

[0048] The thickness of the conductive component 312 is not particularly limited, but for example, it is preferably 1 nm or more and 50 nm or less on average. By setting the average thickness of the conductive component to 1 nm or more, a sufficient amount of the conductive component can be supplied into the resistor film 112, and a conductive path by hopping conduction can be easily formed. Also, by setting the average thickness of the conductive component to 50 nm or less, it is possible to prevent a part of the conductive component from aggregating in the resistor film 112, and the conductive components can be spaced apart at a particularly appropriate distance and arranged discontinuously.

[0049] When measuring the average thickness of the conductive component, first, the glass particles with a coating are made into a state where the cross-section of the particles can be observed by FIB processing or the like. Note that the glass particles with a coating can be embedded in a resin or the like in advance before FIB processing, and cross-section polisher processing or the like can be performed as necessary. Then, using a TEM (transmission electron microscope) or FE-SEM (field emission scanning electron microscope), in the above-mentioned glass particles with a coating, measure the thickness of the conductive component at three or more arbitrary locations, and obtain the average thickness of the conductive component for each particle.

[0050] Similarly, by averaging the average thickness of the conductive component for each particle obtained for 10 or more glass particles with a coating, the average thickness of the conductive component in the glass particles with a coating can be obtained.

[0051] The specific method of disposing the conductive component on at least a part of the surface of the glass particle is not particularly limited, and a vapor phase method such as a sputtering method, a vapor deposition method, or a CVD method, or a wet method such as a sol-gel method can be used. In particular, in the coated glass forming step, it is preferable to dispose the conductive component 312 on the surface of the glass particle 311 by one or more methods selected from the sputtering method and the CVD method. This is because according to the sputtering method and the CVD method, the conductive component can be easily disposed on the surface of the glass particle 311 having a three-dimensional shape, and for example, the control of its film thickness and the like can also be performed. (A) Sputtering method When forming a film of the conductive component on the surface of the glass particle by the sputtering method, it is preferable to use the multi-angle barrel sputtering method.

[0052] The multi-sided barrel sputtering method can be implemented using, for example, the sputtering apparatus 40 shown in FIG. 4. Note that FIG. 4 is a side view of the sputtering apparatus capable of implementing the multi-sided barrel sputtering method, as seen along the rotation axis of the polygonal container 41. The sputtering apparatus 40 can include a polygonal container (barrel) 41, a cathode 42, and a target 43. Further, in order to control the atmosphere during sputtering, it can have a chamber 44. The inside of the chamber 44 can be, for example, evacuated and a gas such as argon can be introduced.

[0053] The polygonal container 41 is configured to be rotatable and swingable along the double arrow B about the rotation axis C in the figure. Note that the cathode 42 and the target 43 are configured not to rotate. For this reason, glass particles (not shown) accommodated in the polygonal container 41 move along with the rotation and swing of the polygonal container 41. However, when the rotation angle of the polygonal container 41 exceeds a certain angle, the glass particles come off the inner peripheral surface of the polygonal container 41 and fall. At that time, the glass particles rotate and the surface facing the target 43 side changes.

[0054] In this way, according to the multi-sided barrel sputtering method, by accommodating glass particles in the polygonal container 41 and rotating and swinging the polygonal container 41, sputtering film formation can be performed while changing the surface of the glass particles facing the target 43 side. Therefore, a uniform film can be formed on the surface of the glass particles.

[0055] Substances such as ruthenium oxide and iridium oxide that undergo volume expansion when oxidized from the metallic state are likely to have the film peeled off from the glass particles when oxidation treatment is performed after the formation of the metal film. Therefore, when forming a ruthenium oxide film or an iridium oxide film by the multi-sided barrel sputtering method or the like as described above, it is preferable to use a ruthenium metal target or an iridium metal target as the target and mix oxygen into the sputtering gas to form the film. By mixing oxygen into the sputtering gas, a ruthenium oxide film or an iridium oxide film can be directly formed on the surface of the glass particles. The content ratio of oxygen in the sputtering gas is not particularly limited, but for example, it is preferably 5% by volume or more and 20% by volume or less.

[0056] It is also conceivable to use a ruthenium oxide or iridium oxide target as the target. However, ruthenium oxide and iridium oxide have sublimability, making it difficult to sinter and manufacture the target. In contrast, targets of ruthenium and iridium, which are metals, can be manufactured by, for example, a melting method by plasma melting. Also, targets of metallic ruthenium and metallic iridium can be manufactured by a hot pressing method, hot isostatic pressing (HIP), etc., using ruthenium metal powder or metallic iridium as a raw material. (B) CVD method (B-1) First form When forming a conductive component on the surface of glass particles by the CVD method, for example, it can be carried out using a film forming apparatus 50 shown in FIG. 5.

[0057] Oxides of iridium and ruthenium, which are materials of the conductive component, that is, IrO 3 and RuO 4 have a high vapor pressure and volatilize at high temperatures. And the above oxides become stable oxides at low temperatures. Specifically, for example, IrO 2 and RuO 2 precipitate as.

[0058] For example, iridium starts to volatilize as a gaseous oxide when it exceeds 1369K, and the main component of the gaseous oxide is IrO 3It is known to be so. And since iridium can be rolled and welded at high temperatures, processed products in the form of plates or cylinders can be easily obtained.

[0059] Therefore, in the case of the film-forming apparatus 50 shown in FIG. 5, an iridium cylinder 52 can be disposed in a refractory reaction vessel 51, and glass particles 55 can be disposed below it. The glass particles 55 can be placed in, for example, a crucible or the like and installed on a porous filter 54. Further, the porous filter 54 can be connected to an exhaust pipe 512.

[0060] Then, while supplying a carrier gas containing oxygen from a gas supply pipe 511 provided above the reaction vessel 51 along the arrow, the iridium cylinder 52 can be high-frequency heated to 1100 K or higher by a high-frequency coil 53 disposed on the outer periphery of the reaction vessel 51. By heating the iridium cylinder 52 while supplying the carrier gas as described above, volatile iridium oxide gas is generated, and IrO is deposited on the surface of the glass particles 55 placed in the low-temperature part. 2 can be deposited as.

[0061] In the reaction vessel 51, the glass particles 55 can be installed at a position below the melting point of the glass particles, preferably in a region of 800 K or lower, and more preferably in a region of 500 K or lower. If necessary, the region where the glass particles 55 of the reaction vessel 51 are disposed can also be cooled by water, wind, or the like.

[0062] Further, in order to uniformly deposit a conductive component on the surface of the glass particles 55 and prevent the generated coated glass particles from adhering to each other, the porous filter 54 is preferably configured to be rotatable by a rotating shaft 56. Furthermore, a screw-type rotating paddle or a baffle plate (not shown) may be installed to stir the glass particles 55.

[0063] IrO 2 After depositing, the gas can be exhausted to the outside through the porous filter 54 and the exhaust pipe 512.

[0064] Here, the case where iridium oxide is deposited as a conductive component on the surface of glass particles has been described as an example. However, by changing the cylinder 52 to ruthenium and adjusting the heating temperature and the like as necessary, ruthenium oxide can be deposited and arranged as a conductive component on the surface of glass particles using the film forming apparatus 50 shown in FIG. 5. (B-2) Second form When the conductive component is formed on the surface of the glass particles by CVD method, for example, it can be carried out using the film forming apparatus 60 shown in FIG. 6.

[0065] As shown in FIG. 6, a film forming raw material 622 serving as a raw material for the conductive component can be placed in a container 621 such as a boat and arranged in the reaction tube 61. For example, when the conductive component is ruthenium oxide, examples of the film forming raw material 622 include metallic ruthenium and ruthenium oxide (RuO 2 ). When the conductive component is iridium oxide, examples of the film forming raw material 622 include metallic iridium and iridium oxide (IrO 2 ).

[0066] Then, while supplying a gas containing oxygen, for example, a mixed gas of an inert gas such as argon and oxygen, along the arrow from one end side of the reaction tube 61, the film forming raw material 622 is heated by a heating device 64 such as a heater, and the film forming raw material 622 can be vaporized. By arranging glass particles 632 installed in the downstream side of the air flow, for example, in the temperature range where the components of the vaporized film forming raw material are deposited, the conductive component can be deposited on the surface of the glass particles. Note that the glass particles 632 can also be placed in a container 631 such as a boat and installed in the reaction tube 61. The glass particles 632 are preferably installed, for example, in a temperature range of 40 ° C or lower.

[0067] In addition, in the film forming apparatus 60, when a material containing ruthenium is used as the film forming raw material as described above, RuO 4 has strong oxidizing properties, so it is preferable not to use an organic material for the part in contact with RuO such as an O-ring or a rubber stopper. 4 (B-3) Third form When forming a film of a conductive component on the surface of glass particles by CVD method, for example, it can be carried out using the film forming apparatus 70 shown in Fig. 7.

[0068] As shown in Fig. 7, a film forming raw material serving as a conductive component can be generated in the reaction vessel 71, and the vaporized film forming raw material can be supplied to the adsorber 76 through the supply pipe 75. Then, by bringing the supplied film forming raw material into contact with and depositing it on the surface of the glass particles 761 installed in the adsorber 76, a conductive component can be formed on the surface of the glass particles 761.

[0069] For example, Ru in an acidic solution is HClO 4 , KIO 4 , NaIO 4 , NaCrO 4 , K 2 Cr 2 O 7 , NaBrO 3 , Ce(SO 4 ) 2 , PbO 2 , KMnO 4 , NaBiO 3 , (NH 4 ) 2 S 2 O 8 KIO 4 When heated with oxidizing agents such as etc., RuO 4 is generated and volatilized.

[0070] Therefore, for example, a reaction solution 711 containing an oxidizing agent and an acidic solution is placed in the reaction vessel 71. The acidic solution is not particularly limited, but for example, when ruthenium chloride is used as the ruthenium source, sulfuric acid can be preferably used because the reaction proceeds easily when sulfuric acid is used as the acidic solution.

[0071] Then, by dropping a ruthenium source, for example, ruthenium chloride, into the reaction solution 711 through the raw material supply pipe 73, RuO 4 can be generated. Note that the reaction solution 711 may be configured as a mixed solution of a ruthenium source and an acidic solution, and an oxidizing agent may be supplied through the raw material supply pipe 73.

[0072] To vaporize the generated RuO 4 and to promote the generation reaction of RuO 4 if necessary, the reaction solution 711 may be heated to, for example, 40 °C or higher by a heating device 72 such as a mantle heater. Further, for the purpose of vaporizing the generated RuO 4 or adjusting the concentration of the film-forming raw material supplied to the adsorber 76, an inert gas such as argon gas can also be blown into the reaction solution 711 through the gas supply pipe 74 or the like.

[0073] Then, the generated and vaporized RuO 4 can be supplied to the adsorber 76 through the supply pipe 75 as described above and brought into contact with and deposited on the surface of the glass particles 761 installed in the adsorber 76. Incidentally, in order to facilitate the deposition of RuO 4 on the surface of the glass particles 761, the adsorber 76 may be cooled, for example, by placing the adsorber 76 in the cooling water in the water tank 77.

[0074] The exhaust gas can be discharged to the outside of the system through the exhaust pipe 78 after passing through an adsorbent 762 such as a molecular sieve disposed on the downstream side of the adsorber 76, for example.

[0075] In the film-forming apparatus 70, when a material containing ruthenium is used as the film-forming raw material as described above, since RuO 4 has strong oxidizing properties, it is preferable not to use organic materials for the portions in contact with RuO 4 such as O-rings and rubber stoppers.

[0076] Here, the case where ruthenium oxide is used as the conductive component has been described as an example, but it is not limited to such a form. For example, when iridium oxide is used as the conductive component, an organometallic compound such as a cyclooctadiene-based iridium compound or a β-diketone-based iridium compound can be vaporized, and iridium oxide can be formed on the surface of the glass particles in the adsorber 76. (2) Paste preparation step In the paste preparation step, conductive particles and coated glass particles can be mixed to prepare a paste for a resistive film.

[0077] Since the conductive particles and the coated glass particles have already been described, the description thereof will be omitted here.

[0078] The content ratio of the conductive particles and the coated glass particles contained in the paste for the resistance film is not particularly limited and can be arbitrarily selected according to the resistance value required for the resistor and the like.

[0079] The resistor obtained by the manufacturing method of the resistor of the present embodiment can have the content ratio of the conductive component in the resistance film be 100 ppm or more and 5000 ppm or less in terms of mass ratio, and the resistance value be 50 Ω or more and 1000 Ω or less. Therefore, according to the average thickness of the conductive component of the coated glass particles used, etc., it is preferable to select the mixing ratio of the conductive particles and the coated glass particles so that the content ratio of the conductive component in the resistance film and the resistance value of the resistor become desired values.

[0080] The mixing ratio of the conductive particles and the coated glass particles is not particularly limited because it can be selected according to the particle size of the conductive particles, the thickness of the conductive component of the coated glass particles, the resistance value required for the resistor, the range of the resistance temperature coefficient, etc. For example, when the total of the conductive particles and the coated glass particles is 100% by mass, it is preferable that the content ratio of the conductive particles be 10% by mass or more and 70% by mass or less. That is, it is preferable that the content ratio of the coated glass particles be 30% by mass or more and 90% by mass or less.

[0081] In the paste preparation step, in addition to the above-mentioned conductive particles and coated glass particles, in order to make a paste, a solvent in which a resin component called a vehicle is dissolved is added, and the conductive particles and the like can be dispersed in the solvent.

[0082] The types and formulations of the resin and solvent of the vehicle are not particularly limited.

[0083] As the resin component, one or more selected from the resin components used in the paste for the resistance film such as ethyl cellulose, maleic acid resin, and rosin can be used.

[0084] As the solvent, one or more selected from solvents used in pastes for resist films such as terpineol, butyl carbitol, and butyl carbitol acetate can be used.

[0085] The resin component used in the vehicle and the blending of the solvent are not particularly limited, and can be selected and adjusted according to the viscosity required for the paste for the resist film. Also, a solvent with a high boiling point can be added to the vehicle for the purpose of delaying the drying of the paste for the resist film.

[0086] The ratio of the vehicle to the composition for the resistor composed of conductive particles and coated glass particles is not particularly limited, but can be, for example, 30% by mass or more and 100% by mass or less in terms of mass ratio.

[0087] The means for preparing the paste for the resist film by dispersing the composition for the thick film resistor in the vehicle is not particularly limited, and for example, one or more selected from a three-roll mill, a planetary mill, a bead mill, etc. can be used.

[0088] In addition, the procedure for preparing the paste for the resist film is not particularly limited. For example, the composition for the thick film resistor may be mixed in advance with a ball mill or a pulverizer and then dispersed in the vehicle.

[0089] When preparing the paste for the resist film, it is preferable to select the dispersion conditions so as to disperse the aggregates of the conductive particles and the like constituting the composition for the thick film resistor and to disperse them sufficiently in the vehicle.

[0090] The resist film can also contain additives for the purpose of adjusting the surface resistance value, the temperature coefficient of resistance, the coefficient of expansion, improving the withstand voltage property, and other modifications. Therefore, additives can also be added to the paste for the resist film as necessary. Since the additives have already been described, the description is omitted here.

[0091] The paste for the resistive film may contain inevitable impurities. Among the impurity ion concentrations, the hydrolyzable chlorine ions are preferably 100 ppm or less, and the metal ions such as alkali are preferably 50 ppm or less. By setting the impurity ion concentration within the above range, bleeding of the paste during bonding of electronic components can be prevented, and characteristics such as adhesive strength, heat resistance, moisture resistance, heat cycle resistance, conductivity, and workability can be particularly enhanced.

[0092] In addition to the above-described components, the paste for the resistive film may contain, if necessary, a curing accelerator such as blocked isocyanate, a silane coupling agent or a titanate coupling agent for improving the bonding strength, and a coloring agent such as a pigment or a dye. (3) Resistive film forming step In the resistive film forming step, a resistive film can be formed by applying the paste for the resistive film between a pair of electrodes.

[0093] Specifically, a resistor can be formed by applying the paste for the resistive film between a pair of electrodes previously formed on an insulating substrate, followed by drying and heat treatment.

[0094] The coating conditions at this time are not particularly limited and can be selected according to the composition of the paste for the resistive film and the characteristics required for the resistor.

[0095] Also, the conditions for drying and heat treatment are not particularly limited, and the drying and heat treatment conditions can be selected according to each component contained in the paste for the resistive film. The drying and heat treatment temperature is preferably equal to or higher than the softening point of the glass contained in the glass particles with a coating, for example, preferably 650°C or higher and 900°C or lower. For example, the temperature can be raised from room temperature to the heat treatment temperature, held at a constant temperature for 10 minutes or more and 2 hours or less at the heat treatment temperature, and then taken out of the furnace and allowed to cool naturally.

[0096] Figure 3 shows a schematic cross-sectional view of the conductive particles 13 and the coated glass particles 31 contained in the paste for a resistive film 30 obtained in the paste preparation process described below, taken at an arbitrary cross-section. As shown in Figure 3, the coated glass particles 31 can have glass particles 311 and a conductive component 312 disposed on at least a part of the surface of the glass particles 311.

[0097] Then, in the resistive film forming process, by drying and heat-treating the paste for a resistive film, the glass particles 311 of the coated glass particles 31 soften, and as shown in Figure 1, the glass 12 spreads around the conductive particles 13 to form the resistive film 112.

[0098] Also, when heat treatment is performed, the conductive component 312 disposed on the surface of the coated glass particles 31 is disposed at the grain boundaries of the coated glass particles 31, and a conductive path by hopping conduction can be formed. Even if the conductive component 312 is formed in a film shape on the surface of the glass particles 311, when heat treatment is performed, the film is broken and is discontinuously and separately disposed in the resistive film.

Examples

[0099] Specific examples, comparative examples, etc. will be given below for explanation, but the present invention is not limited to these examples. (Evaluation method) The evaluation method of the resistors manufactured in the following examples and comparative examples will be described. (1) Resistance value measurement For the film thickness, for 5 resistors manufactured under the same conditions in each example and comparative example, the film thickness was measured using a stylus thickness roughness meter (manufactured by Tokyo Seimitsu Co., Ltd., model number: Surfcom 480B), and the calculated value was obtained by averaging the measured values.

[0100] For the 5 manufactured resistors, the resistance value was measured using a digital multimeter (manufactured by KEITHLEY, model number 2001), and the obtained resistance value was converted to the case where the thickness of the resistor is 6 μm. Then, the average of the resistance values of the 5 thick film resistors after conversion was taken as the resistance value of the thick film resistor. (2) Temperature coefficient of resistance The temperature coefficient of resistance was calculated by the following procedure.

[0101] Five resistors with a width of 1 mm and a length of 10 mm were fabricated under the same conditions in each of the following examples and comparative examples. After each resistor was held at -55°C, 25°C, and 125°C for 15 minutes respectively, the resistance value was measured. The resistance values of each thick-film resistor at each temperature are R -55 , R 25 , R 125 . For example, R -55 means the resistance value at -55°C.

[0102] Next, for each thick-film resistor, the low-temperature side temperature coefficient of resistance COLD-TCR and the high-temperature side temperature coefficient of resistance HOT-TCR were calculated by the following formulas (A) and (B), and the average of the five resistors was used as the temperature coefficient of resistance (COLD-TCR, HOT-TCR) of the thick-film resistor in each example and comparative example. COLD-TCR (ppm / °C) = (R -55 -R 25 ) / R 25 / (-80) × 10 6 ···(A) HOT-TCR (ppm / °C) = (R 125 -R 25 ) / R 25 / (100) × 10 6 ···(B) Note that it is desirable that the temperature coefficient of resistance be close to 0, and a resistance body with -100 ppm / °C ≤ temperature coefficient of resistance ≤ 100 ppm / °C is regarded as an excellent standard. (3) Content ratio of conductive component Regarding the content ratio of the conductive component in the obtained resistance film, it was evaluated by ICP emission spectrometry using an ICP emission spectrometer (manufactured by Shimadzu Corporation, model: ICPS8100). (Manufacturing conditions) [Experimental Example 1] [Example 1-1] (Coated glass particle formation process) Glass powder with an average particle size of 1.5 μm was placed in a sputtering apparatus 40 by the polygonal barrel sputtering method shown in Fig. 4, and the barrel rotation speed was set to 0.1 rpm. That is, the rotary shaft C was rotated at a rate of 120 degrees around the center of rotation in 200 seconds. The degree of vacuum in the chamber 44 before sputtering was 2×10 -4 Pa, and as the sputtering gas, an Ar:O 2 mixed gas was used, and the flow rate ratio was Ar:O 2 =9:1.

[0103] Then, a ruthenium oxide film was formed on the surface of the insulating particles to an average thickness of 2 nm. When the evaluation was carried out, it was confirmed that the thickness of the ruthenium oxide film of the obtained coated particles was 2 nm.

[0104] When measuring the thickness of the ruthenium oxide film, first, the coated particles were embedded in resin, cross-section polisher processing was performed, then FIB (focused ion beam) processing was performed, and cross-sectional observation of the particles was performed by TEM (transmission electron microscope). Then, in the coated glass particles in the above resin, the thickness of the ruthenium oxide film was measured at three arbitrary locations, and the average thickness of the ruthenium oxide film for each particle was obtained.

[0105] Similarly, by averaging the average thickness of the ruthenium oxide film for each particle obtained for 10 coated glass particles, the thickness of the ruthenium oxide film in the coated glass particles was obtained.

[0106] As the glass particles, particles of glass containing each component in a ratio of SiO 2 : 35% by mass - B 2 O 3 : 20% by mass - Al 2 O 3 : 5% by mass - CaO: 5% by mass - BaO: 20% by mass - ZnO: 15% by mass were used. (Paste preparation process) Ag powder with an average particle size of 1.0 μm, Pd powder with an average particle size of 0.3 μm, and the coated glass particles were dispersed in a vehicle composed of 10% by mass of ethyl cellulose and 90% by mass of terpineol using a three-roll mill to prepare a paste for a resistive film.

[0107] In addition, when mixing, the compounding ratio of Ag powder, Pd powder, and coated glass particles was set to Ag powder:Pd powder:coated glass particles = 40:17:43 by mass ratio. (Resistive film formation process) The paste for a resistive film obtained in the paste preparation process was applied onto an alumina substrate on which a pair of electrodes had been previously formed through a mask, with a width of 1 mm and a length of 10 mm, and the average film thickness of the coating film was 10 μm. The electrodes were prepared in advance using Ag paste.

[0108] After leaving the above coating film at room temperature for 30 minutes, it was heated and dried at 150 °C for 5 minutes in an electric oven. Then, it was heated to 850 °C in 15 minutes and held at 850 °C for 10 minutes. The film thickness after firing was 5.9 μm to 6.2 μm.

[0109] Regarding the obtained resistor, the resistance value, temperature coefficient of resistance, and content of the conductive component were evaluated. The evaluation results are shown in Table 1. [Example 1-2] In the paste preparation process, the compounding ratio of Ag powder, Pd powder, and coated glass particles was set to Ag powder:Pd powder:coated glass particles = 15:1:84 by mass ratio. Except for the above points, a paste and a resistor were prepared and evaluated in the same manner as in Example 1-1.

[0110] The evaluation results are shown in Table 1. [Comparative Example 1-1] In the paste preparation process, the compounding ratio of Ag powder, Pd powder, and coated glass particles was set to Ag powder:Pd powder:coated glass particles = 44:32:24 by mass ratio. Except for the above points, a paste and a resistor were prepared and evaluated in the same manner as in Example 1-1.

[0111] The resistance value of the obtained resistor was measured, but there was no conductivity, and the resistance value and the temperature coefficient of resistance could not be measured. [Experimental Example 2] [Example 2-1] (Coated glass particle formation step) Glass powder with an average particle size of 1.5 μm was put into a sputtering apparatus 40 by the polygonal barrel sputtering method shown in FIG. 4, and the barrel rotation speed was set to 0.1 rpm. That is, the rotary shaft C was rotated at a rate of 120 degrees around the center of rotation in 200 seconds. The degree of vacuum in the chamber 44 before sputtering was 2×10 -4 Pa, and as the sputtering gas, an Ar:O 2 mixed gas was used, and the flow rate ratio was Ar:O 2 = 9:1.

[0112] Then, an iridium oxide film was formed on the surface of the insulating particles to an average thickness of 2 nm. When evaluated, it was confirmed that the film thickness of the iridium oxide film of the obtained coated particles was 2 nm.

[0113] The measurement of the film thickness of the iridium oxide film was carried out in the same manner as in the case of Example 1-1.

[0114] As the glass particles, glass particles containing each component in a ratio of SiO 2 : 35% by mass - B 2 O 3 : 20% by mass - Al 2 O 3 : 5% by mass - CaO: 5% by mass - BaO: 20% by mass - ZnO: 15% by mass were used. (Paste preparation step) Ag powder with an average particle size of 1.0 μm, Pd powder with an average particle size of 0.3 μm, and the above-mentioned coated glass particles were dispersed in a vehicle composed of 10% by mass of ethyl cellulose and 90% by mass of terpineol by a three-roll mill to prepare a paste for a resistive film.

[0115] When mixing, the compounding ratio of Ag powder, Pd powder, and coated glass particles was set to Ag powder:Pd powder:coated glass particles = 40:17:43 by mass ratio. (Resistance film formation process) The resistance film paste obtained in the paste preparation process was applied onto an alumina substrate on which a pair of electrodes had been previously formed, through a mask, with a width of 1 mm and a length of 10 mm, and the average film thickness of the coating film was 10 μm. The electrodes were previously fabricated using Ag paste.

[0116] After leaving the above coating film at room temperature for 30 minutes, it was heated and dried in an electric oven at 150 °C for 5 minutes. Then, it was heated to 850 °C in 15 minutes and held at 850 °C for 10 minutes.

[0117] For the obtained resistor, the resistance value, temperature coefficient of resistance, and content of the conductive component were evaluated. The evaluation results are shown in Table 1. [Example 2-2] In the paste preparation process, the compounding ratio of Ag powder, Pd powder, and coated glass particles was set to Ag powder:Pd powder:coated glass particles = 15:1:84 by mass ratio. Except for the above points, the paste and resistor were fabricated and evaluated in the same manner as in Example 1-1.

[0118] The evaluation results are shown in Table 1. [Comparative Example 2-1] In the paste preparation process, the compounding ratio of Ag powder, Pd powder, and coated glass particles was set to Ag powder:Pd powder:coated glass particles = 44:32:24 by mass ratio. Except for the above points, the paste and resistor were fabricated and evaluated in the same manner as in Example 1-1.

[0119] The resistance value of the obtained resistor was measured, but there was no conduction, and the resistance value and temperature coefficient of resistance could not be measured. [Experimental Example 3] [Example 3-1] (Coated glass particle formation process) 55 glass particles with an average particle size of 1.5 μm were placed in a crucible and placed on the porous filter 54 in the reaction vessel 51 of the film forming apparatus 50 shown in FIG. 5.

[0120] Then, in order to prevent the vaporization of iridium during heating, Ar gas was flowed into the reaction vessel 51 from the gas supply pipe 511 at a rate of 2 L / min, and the iridium cylinder 52 installed in the reaction vessel 51 was heated to 1573 K by the high-frequency coil 53.

[0121] Next, the gas supplied from the gas supply pipe 511 was switched to a mixed gas of 90 vol% Ar gas - 10 vol% O 2 gas, and heating at the above temperature was continued. As a result, the oxide of iridium was vaporized, and IrO 2 was deposited on the surface of the glass particles 55.

[0122] In addition, the lower part of the reaction vessel 51 was water-cooled so that the temperature of the reaction vessel 51 around the crucible containing the glass particles 55 would be 400 K or lower. Also, the temperature of the cylinder 52 was measured by a radiation thermometer.

[0123] The heating time was adjusted so that the average thickness of the iridium oxide film on the surface of the glass particles was 2 nm, and the film was formed. When evaluated, it was confirmed that the film thickness of the iridium oxide film of the obtained coated glass particles was 2 nm.

[0124] The measurement of the film thickness of the iridium oxide film was carried out in the same manner as in Example 1-1.

[0125] As the glass particles, SiO 2 : 35 mass% - B 2 O 3 : 20 mass% - Al 2 O 3 : 5 mass% - CaO: 5 mass% - BaO: 20 mass% - ZnO: 15 mass% of glass particles containing each component in the ratio were used. (Paste preparation process) Ag powder with an average particle size of 1.0 μm, Pd powder with an average particle size of 0.3 μm, and the coated glass particles were dispersed in a vehicle composed of 10% by mass of ethyl cellulose and 90% by mass of terpineol using a three-roll mill to prepare a paste for a resistive film.

[0126] In addition, when mixing, the blending ratio of the Ag powder, Pd powder, and coated glass particles was 40:17:43 by mass ratio, i.e., Ag powder:Pd powder:coated glass particles = 40:17:43. (Resistive film formation step) The paste for a resistive film obtained in the paste preparation step was applied onto an alumina substrate on which a pair of electrodes had been previously formed through a mask, with a width of 1 mm and a length of 10 mm, and the average film thickness of the coating film was 10 μm. The electrodes were previously prepared using an Ag paste.

[0127] After leaving the above coating film at room temperature for 30 minutes, it was heated and dried at 150 °C for 5 minutes in an electric oven. Then, it was heated to 850 °C in 15 minutes and held at 850 °C for 10 minutes.

[0128] For the obtained resistor, the resistance value, temperature coefficient of resistance, and content of the conductive component were evaluated. The evaluation results are shown in Table 1. [Example 3-2] In the paste preparation step, the blending ratio of the Ag powder, Pd powder, and coated glass particles was 15:1:84 by mass ratio, i.e., Ag powder:Pd powder:coated glass particles = 15:1:84. Except for the above points, a paste and a resistor were prepared and evaluated in the same manner as in Example 1-1.

[0129] The evaluation results are shown in Table 1. [Comparative Example 3-1] In the paste preparation step, the blending ratio of the Ag powder, Pd powder, and coated glass particles was 44:32:24 by mass ratio, i.e., Ag powder:Pd powder:coated glass particles = 44:32:24. Except for the above points, a paste and a resistor were prepared and evaluated in the same manner as in Example 1-1.

[0130] The resistance value of the obtained resistor was measured, but there was no conduction, and the resistance value and the temperature coefficient of resistance could not be measured. [Experimental Example 4] [Example 4-1] (Coated glass particle formation step) Using the film forming apparatus 60 shown in FIG. 6, coated glass particles were formed.

[0131] ZrO 2 The film forming raw material 622 which is a raw material of the conductive component was put into the container 621 which is a dish made of ZrO, and it arrange | positioned in the quartz tube which is the reaction tube 61. As the film forming raw material, RuO having an average particle diameter of 0.5 μm 2 powder was used.

[0132] Then, from one end side of the reaction tube 61, along the arrow, while supplying a mixed gas of 90% by volume of Ar gas - O 2 10% by volume of gas, the film forming raw material 622 was heated by the heating device 64 which is a mantle heater, the film forming raw material 622 was vaporized, and RuO was supplied into the air stream 4 was supplied.

[0133] On the downstream side of the air stream, glass particles 632 put into the container 631 which is a dish made of ZrO in advance were arranged, and by blowing the air stream containing the above RuO 2 RuO was adsorbed on the surface of the glass particles 632. In this Example, unlike the film forming apparatus 60 of FIG. 6, the glass particles 632 put into the container 631 were connected to the reaction tube 61 by piping and put into a quartz flask, and the quartz flask was put into a water tank filled with water at 25 ° C., and the above adsorption was performed while cooling. 4 was adsorbed. 4 Since RuO

[0134] RuO 4 is unstable at room temperature, oxygen desorbs and RuO 2 is formed. However, as a precaution, it was held at 150 ° C. for 1 hour in the air on a hot plate to remove RuO 4 (boiling point 129 ° C.), and glass particles to which RuO 2 was attached were produced.

[0135] RuO 2 RuO was formed on the surface of glass particles based on the film-forming conditions (film-forming time) determined in preliminary tests so that the average thickness of the ruthenium oxide film was 2 nm. As a result of evaluation, it was confirmed that the thickness of the ruthenium oxide film of the obtained coated glass particles was 2 nm.

[0136] The thickness of the ruthenium oxide film was measured in the same manner as in Example 1-1.

[0137] As the glass particles, particles of a glass containing each component in a ratio of SiO 2 : 35% by mass - B 2 O 3 : 20% by mass - Al 2 O 3 : 5% by mass - CaO: 5% by mass - BaO: 20% by mass - ZnO: 15% by mass were used. (Paste preparation process) Ag powder with an average particle size of 1.0 μm, Pd powder with an average particle size of 0.3 μm, and the above-mentioned coated glass particles were dispersed in a vehicle composed of 10% by mass of ethyl cellulose and 90% by mass of terpineol with a three-roll mill to prepare a paste for a resistive film.

[0138] When mixing, the blending ratio of Ag powder, Pd powder, and coated glass particles was Ag powder: Pd powder: coated glass particles = 40:17:43 by mass ratio. (Resistive film formation process) The paste for a resistive film obtained in the paste preparation process was applied onto an alumina substrate on which a pair of electrodes had been previously formed through a mask, with a width of 1 mm and a length of 10 mm, and the average film thickness of the coating film was 10 μm. The electrodes were previously prepared using Ag paste.

[0139] After leaving the above coating film at room temperature for 30 minutes, it was heated and dried in an electric oven at 150 °C for 5 minutes. Then, it was heated to 850 °C in 15 minutes and held at 850 °C for 10 minutes.

[0140] For the obtained resistor, the resistance value, the temperature coefficient of resistance, and the content of the conductive component were evaluated. The evaluation results are shown in Table 1. [Example 4-2] In the paste preparation step, the blending ratio of Ag powder, Pd powder, and coated glass particles was such that the mass ratio was Ag powder:Pd powder:coated glass particles = 15:1:84. Except for the above points, the paste and resistor were prepared and evaluated in the same manner as in Example 1-1.

[0141] The evaluation results are shown in Table 1. [Comparative Example 4-1] In the paste preparation step, the blending ratio of Ag powder, Pd powder, and coated glass particles was such that the mass ratio was Ag powder:Pd powder:coated glass particles = 44:32:24. Except for the above points, the paste and resistor were prepared and evaluated in the same manner as in Example 1-1.

[0142] The resistance value of the obtained resistor was measured, but there was no conduction, and the resistance value and the temperature coefficient of resistance could not be measured. [Experimental Example 5] [Example 5-1] (Coated Glass Particle Formation Step) Using the film-forming apparatus 70 shown in FIG. 7, coated glass particles were formed.

[0143] Into a reaction vessel 71, which is a four-necked flask with a capacity of 2000 mL, 1.8 L of a 0.5 M sulfuric acid solution, which is an acidic solution, was placed, and further 50 g of KIO, which is an oxidizing agent 3 (manufactured by Fujifilm Wako Pure Chemical Corporation) was added to obtain a reaction solution 711.

[0144] The reaction vessel 71 was placed in a heating device 72, which is a mantle heater, and the reaction solution 711 was heated to 96°C.

[0145] On the other hand, RuCl was prepared in advance 3 ·3H 2O (manufactured by FUJIFILM Wako Pure Chemical Corporation) was dissolved in a 0.5 M sulfuric acid solution and placed in a dropping funnel. Note that the raw material supply pipe 73 in Fig. 7 was used as the dropping funnel. Then, from the dropping funnel, a solution in which ruthenium chloride was dissolved in a sulfuric acid solution was dropped into the reaction solution 711 at a rate of 12 mg / hour in terms of the amount of Ru.

[0146] Argon gas was blown into the reaction vessel 71 from the gas supply pipe 74, and the generated and vaporized RuO 4 was supplied to the adsorber 76 through the supply pipe 75 and brought into contact with and deposited on the surface of the glass particles 761 with an average particle size of 1.5 μm installed in the adsorber 76. Note that in order to facilitate the deposition of RuO 4 on the surface of the glass particles 761, the adsorber 76 was placed in the water at 25 °C stretched in the water tank 77 to cool the adsorber 76.

[0147] The exhaust gas was discharged to the outside of the system through the exhaust pipe 78 after passing through the adsorbent 762, which is a molecular sieve, arranged on the downstream side of the adsorber 76, for example.

[0148] RuO 4 is unstable at room temperature, so oxygen desorbs to form RuO 2 However, as a precaution, it was held at 150 °C in the air on a hot plate for 1 hour to remove RuO 4 (boiling point 129 °C) to produce glass particles with RuO 2 adhered.

[0149] RuO 2 was formed on the surface of the glass particles based on the film formation conditions (film formation time) obtained in preliminary tests so that the average thickness of the ruthenium oxide film was 2 nm. Note that when evaluation was carried out, it was confirmed that the film thickness of the ruthenium oxide film possessed by the obtained coated glass particles was 2 nm.

[0150] The measurement of the film thickness of the ruthenium oxide film was carried out in the same manner as in the case of Example 1-1.

[0151] As the glass particles, SiO 2 : 35 mass% - B2 O 3 : 20 mass%-Al 2 O 3 : Glass particles containing each component in a ratio of 5 mass%-CaO: 5 mass%-BaO: 20 mass%-ZnO: 15 mass% were used. (Paste preparation step) Ag powder with an average particle size of 1.0 μm, Pd powder with an average particle size of 0.3 μm, and the above-mentioned coated glass particles were dispersed in a vehicle composed of 10 mass% ethyl cellulose and 90 mass% terpineol using a three-roll mill to prepare a paste for a resistive film.

[0152] When mixing, the blending ratio of Ag powder, Pd powder, and coated glass particles was, by mass ratio, Ag powder: Pd powder: coated glass particles = 40: 17: 43. (Resistive film formation step) The paste for a resistive film obtained in the paste preparation step was applied onto an alumina substrate on which a pair of electrodes had been previously formed through a mask, with a width of 1 mm and a length of 10 mm, and the average film thickness of the coating film was 10 μm. The electrodes were previously fabricated using Ag paste.

[0153] After leaving the above coating film at room temperature for 30 minutes, it was heated and dried in an electric oven at 150 °C for 5 minutes. Then, it was heated to 850 °C in 15 minutes and held at 850 °C for 10 minutes.

[0154] For the obtained resistor, the resistance value, the temperature coefficient of resistance, and the content of the conductive component were evaluated. The evaluation results are shown in Table 1. [Example 5-2] In the paste preparation step, the blending ratio of Ag powder, Pd powder, and coated glass particles was, by mass ratio, Ag powder: Pd powder: coated glass particles = 15: 1: 84. Except for the above points, a paste and a resistor were prepared and evaluated in the same manner as in Example 1-1.

[0155] The evaluation results are shown in Table 1. [Comparative Example 5-1] In the paste preparation process, the blending ratio of Ag powder, Pd powder, and coated glass particles was set to Ag powder:Pd powder:coated glass particles = 44:32:24 by mass ratio. Except for the above points, the paste and resistor were prepared and evaluated in the same manner as in Example 1-1.

[0156] In addition, the resistance value of the obtained resistor was measured, but there was no conduction, and the resistance value and the temperature coefficient of resistance could not be measured.

[0157]

Table 1

Explanation of Symbols

[0158] 10 Resistor 111 Electrode 112 Resistance Film 12 Glass 13 Conductive Particles 14, 312 Conductive Component 30 Paste for Resistance Film 31 Coated Glass Particles 311, 55, 632, 761 Glass Particles

Claims

1. A coated glass particle forming step of disposing a conductive component, which is ruthenium oxide or iridium oxide, on at least a part of the surface of glass particles to form coated glass particles; A paste preparation step of mixing one or more kinds of conductive particles selected from gold, silver, and palladium and the coated glass particles to prepare a paste for a resist film; A resist film forming step of applying the paste for a resist film between a pair of electrodes to form a resist film, and having: A method for manufacturing a resistor, wherein the content ratio of the conductive component in the resist film is 100 ppm or more and 5000 ppm or less by mass ratio, and the resistance value is 50 Ω or more and 1000 Ω or less.

2. The method for manufacturing a resistor according to claim 1, wherein in the coated glass particle forming step, the conductive component is disposed on the surface of the glass particles by one or more methods selected from a sputtering method and a CVD method.

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